Polyp Retrieval after Cold Snare Polypectomy: A Randomized Controlled Trial of Simple Suction versus Cap-Assisted Water-Infused Suction

Abstract Specimen retrieval after cold snare polypectomy (CSP) for small colorectal polyps can be difficult because resected specimens are often small and soft. We compare the efficacy of simple suction with cap-assisted water-infused suction for specimen retrieval after CSP. This prospective randomized controlled trial enrolled patients undergoing CSP for colorectal polyps ≤10 mm. Patients were randomly assigned to either simple suction (Group A) or cap-assisted water-infused suction (Group B) for specimen retrieval. The primary outcome was specimen retrieval time. Secondary outcomes included retrieval rates and procedure-related complications. A total of 141 patients with 387 colorectal polyps were analyzed. Group A and Group B included 198 and 189 polyps from 66 and 75 patients, respectively. The primary outcome, mean retrieval time, was significantly shorter in Group B than in Group A (17.2 ± 11.7 vs. 35.8 ± 66.4 s; patient-clustered p = 0.0028). Median retrieval times were 15 and 22 s in Groups B and A, respectively (median difference, Group B minus Group A, −7 s; patient-level cluster-bootstrap 95% CI: −11 to −5). Retrieval rates were high in both groups (100 vs. 99.5%, p = 0.488). Immediate bleeding occurred in 2.0% and 4.8% of cases in Groups A and B, respectively, whereas no delayed bleeding or perforation occurred in either group. Cap-assisted water-infused suction significantly reduced specimen retrieval time among successfully retrieved specimens after CSP for small colorectal polyps. Effects on specimen integrity and histologic quality require further evaluation.